Spring connector for printed circuit board



Oct. 25, 1966 R. H. BLAIR SPRING CONNECTOR FOR PRINTED CIRCUIT BOARD Filed Aug. 30, 1963 FICJ.

INVENTOR. RAYMOND H. BLAIR ATTY.

United States Patent O Filed Aug. 30, 1963, Ser. No. 305397 2 Claims. (CI. 339-17) The ;invention described herein may be manufactured and used by or for the Government of the United States of America tor .governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a means for connecting electrical and electrical-mechanical Components to ojrcuit boards or electric cirouitry and more particularly to a coiled spring electrical connecter.

In the field of .connecting e lectnical-mechanical components to ci-rou-it boards or electrical -circuit ry, it has been the general practice to employ a coiled spring housed wi-thin the circuit board and a plug h-oused with-in the component so that the plug may 'be .inserted into the coiled .spring ;in order to make an electrical connection. Vario-us types of spring clips have been soldered to the circuit board and are insertable in a socket housed with-in the component. Also vanious types of complex cab ling systems have been used to connect a circuit board to a c-omponent. Although such devices have .served the purpose, they have not proved entirely satisfactory under all conditions of service for the reasons that considerable difficulty has been experienced in repair-ing defective connections. It has been found that the sub-miniature connectors required too much space for engaging, disengaging and the cablin g. Prior devices have also required complex cab-ling systems, have been very expensive and not too reli-able in operation.

The general purpose of this invention is to provide a coiled spring electrical connector which embraces all the advantages of similarly employed electrical connectors and possesses none of the -aforedescribed disadvantages. To attain this purpose, the present inventi-on contemplates a unique coiled spring electrica l connector insertable by a special tool into a circuit board having an eyelet therein and then into an insulated socket housed within the base or side of a component. The coiled spring electrical connector provides a method of connecting and interconnecting a number of elements such that much -less space is required than by using standard connectors and cabling. In the instant i-nve-nt-ion, complex cabiing systems are eliminated, cost is reduced and high reli-ability is obtained.

An object of the present invention is the provision of a new and improved e lectrical oonnector.

Another object of this invention 'is to provide a new and improved coiled spring e lectrical conneotor suitable for use in printed ci rcuit boards.

A further object of the invention is the provision of a reliable, flexible and tight-fitt ing electrical connection.

Other objects and features of the invention will become apparent -as the disclosure is made in the following detailed description of a preferred embodiment of the invention as illustrated in the acconpanying sheet of drawing tin which:

FIG. 1 is `a cross-sectional view of a circuit board and the component showing a coiled spring electrica-l connector being inserted by a tool into both elements, and another connecter in the inserted position; and

FIG. 2 is another embodiment of the invention in which a coi-led .spring connector is shown c-onnecting two printed circuit boards.

3,28L751 Patented Oct. 25, 1966 Referring now to the drawing, wherein like reference characters designate like or correspond-ing parts throughout the views, there is shown in FIG. 1 a oircuit board 1 having a printed circuit -on one or two .sides thereof. Spaced adjacent t-o the circuit board l is a Component 2. A coiled spring electrica-l connector 3 connec-ts the circuit board 1 to the insulated socket 5 in bas-e 8 of Component 2. Eyelets 4 are inserted -in openings 13 located in the cirouit board 1. Sockets 5 having apertures therein oi approximate ly the same diameter as apertures in the eyelets are inserted through -openin-gs -14 in the base 8. These sockets can be he-rmeti-cally sealed in the base or insulated from the base, if .so desired. The coiled spring connector 3 has a normal diameter which is slightly larger than the diameter of the apertures of the eye-lets 4 and sockets 5. Wi-res 6 are Wrapped around the pins of sockets S to complete the electrical circuit. The wires are connected to electrica-l and electrical-mechanical components such as resistors, capacitors, re lays, accelerometers, timers and switches (not shown). Spacer'; 15 separate the circuit board 1 from the base 8. A too'i for inse-rting and removing the coil spring Connector 3 comprises a knurled knob 9, rod 10 and cy lindrical member 11 rotatab'le on the rod. At one end of the ro d 10 is a -shaped portion 17 for grasping one end of :the coiled spring connect-or 3. The r od 10 is inserted into the cylindri-cal 'member 11 which has a hole 16 therein for receiving the rod 10. The cylindr--c-al member 11 has au extension 12 thereon for grasping the other end of the coil spring connector 3.

The coiled spring electrical connect-or is connected and dis-connected in the following manner. The rod in nserted into the coiled spring 3 and one end of the coiled spring Connector 3 is attached to the U-shaped end 17 of the rod 10. The other end of the coiled spring oonnector 3 is attached to the extension 12 of the cy-lindrical member 11. The cy lind-rical member 1-1 is rotated with respect to the knob 9 and rod 10 thereby twisting the coils tighter and reducing the diameter of the coiled spring Connector 3. While the coiled spring Connector is in this reduced condition, it is inserted through the eyelet 4 in the -ci rcuit board l and then into the -insulated socket 5 in base 8. The cylindrieal member 11 is rotated back to its initial position and disconnected from the coiled spring connecter, and the rod 10 is also dis-connected from the `coiled spring connecter thereby allowing the coil to expand and flexibly connect the circuit board 1 to the socket 5 in base 8. An electrical circuit is now completed between the c-ircuit board Il, eye-let 4, coiled spning connector 3, insulated socket 5 and wire 6. Thus it can be seen that there is shown on FIG. 1 a tool for inserting a coiled .spring connect-or and a coiled spring connector in the connecting position afte-r the tool has been removed. If it is desired to (remove the coiled spring connector, the tool is connected to both ends of the coiled spring connector 3, rotated so that the diameter of the connect-or s reduced, and then :the connector is with drawn from the socket 5 and the eyelet 4.

It is to be understood that the coil diameter and the wire diameter of the c-oiled spring connecter may be varied depending on the current to be carried. Also, the capaoity of the spring connection can be increased by inserting an electrical conducting exible core inside the coil after the coil has been inserted into the circuit board and the base. F-urther, the elements t-o be connected by the coiled spring connector can be varied t-o mee-t the function desired. For example, FIG. 2 shows a coiled spring electnical connecter 3 in electrically connecting engagement with a circuit board 18 and a circuit board 19, each board having a printed circuit thereon. The coiled spring connector or a plurali-ty of them can be used to interconnect any number of printed eireuit boards or printed circuit boards in co'mbinati-on With a component. Each circuit board can be constructed With a pri-nted circui-t on each side -or inte-rnally thereof, if desired.

I-t can be seen that a unique coi led spring eleetrical connecter has been provided :to electrically connect a c-ircuit board to -a Component. A coiled spring electrical connect or has been provided that makes :a :flexib-ie, t-ightfitting electrical connection between a circuit board and a oomponen-t and is reiiabie in operation.

Obviously many modifications and variations of :the present inve-ntion are possible in the light of the above teachings. It is therefore -to be understood, that within the .scope of the appended claims, the inven-ti on may be practiced otherwise th-an as specificai ly described.

What is claimed is: 1. An electricai interconnect-ing device for interoonnecting an insulatin g board having a -prnted circuit thereon with at least one terminal to the base of an eleetrical component having at least one terminal t-hereon, said c-onnectin-g device comprising:

a tubular conductive eyel et extending through said board and in electricaily conducting engagement With a terminal of said printed circuit,

an -insuiated conductiv-e socket closed at -one end located in the base of said component and in electr-icai ly conducting engagement with a terminal thereon,

and an electri-oally conductive coiled spring having a normal coi-1 diameter throughout its .length slightly lar-ger than the internal diameters of said eyelet and References Cited by the Examiner UNITED STATES PATENTS 1,023,270 4/1912 Nungesser 339-256 1,334,040 3/1920 Lee 339-252 2,752,580 6/1956 Shewrnaker 339-17 2,792,560 5/1957 Bol lmeier 339--252 3,022,369 2/ 1962 Rayburn 339-17 X FOREIGN PATENTS 227,1 01 12/ 1925 Great Britain.

OTHER REFERENCES i Kennedy et ai.: I.B.M. Technical Disciosure B-ul-letin. June 1963, pages 36 and 37.

EDWARD C. ALLEN, Pr'mary Exam'ner- ALFRED S. TRASK, Examiner. 

1. AN ELECTRICAL INTERCONNECTING DEVICE FOR INTERCONNECTING AN INSULATING BOARD HAVING A PRINT CIRCUIT THERE ON WHICH AT LEAST ONE TERMINAL TO THE BASE OF AN ELECTRICAL COMPONENT HAVING AT LEAST ONE TERMINAL THEREON, SAID CON NECTING DEVICE COMPRISING: A TUBULAR CONDUCTIVE EYELET EXTENDING THROUGH SAID BOARD AND IN ELECTRICALLY CONDUCTING ENGAGEMENT WITH A TERMINAL OF SAID PRINTED CIRCUIT, AN INSULATED CONDUCTIVE SOCKET CLOSED AT ONE END LOCATED IN THE BASE OF SAID COMPONENT AND ELECTRICALLY CONDUCTING ENGAGEMENT WITH A TERMINAL THEREON, AND AN ELECTRICALLY CONDUCTIVE COILED SPRING HAVING A NORMAL COIL DIAMETER THROUGHOUT ITS LENGTH SLIGHTLY LARGER THAN THE INTERNAL DIAMETERS OF SAID EYELET AND SAID SOCKET AND CAPABLE OF BEING REDUCED IN DIAMETER FOR PERMITTING INSERTION THROUGH SAID EYELET AND INTO SAID SOCKET AND THEREAFTER BEING EXPANDED TO RESILIENTLY ENGAGE THE INNER WALLS OF SAID EYELET AND SAID SOCKET, THEREBY ELECTRICALLY CONNECTING THE PRINTED CIRCUIT TERMINAL TO THE TERMINAL OF THE ELECTRICAL COMPONENT. 